Abstract:Rotor speed control of wind turbines is a key factor in achieving the maximum power of wind. It is known that a high-performance controller can significantly increase the amount of energy that can be captured from this source. The main problem regarding this issue is the lack of information about the correct dynamic model of the system. This uncertainty of the model is generally associated with unknown parameters (structured uncertainty) and/or external disturbances (unstructured uncertainty). Some adaptive an… Show more
“…The WTFS cannot capture the maximum power of the wind in various wind speeds (Poultangari et al, 2012) and hence, WTVS is developed in recent years (Oh et al, 2015). The strategy to obtain the maximum power of the wind by WTVS, is based on dividing the operation performance using the rated speed of the wind (Jabbari Asl and Yoon, 2016). Below this rated wind speed, the torque of generator is controlled for the maximum power point tracking (MPPT) (Ardjal et al, 2018), and above this rated wind speed, the pitch angle of the blades (PABLE) is used as the input control (Asgharniaa et al, 2018).…”
In a wind turbine (WT), the maximum power can be achieved using a suitable and smooth signal, which should be applied to the pitch angle of the blades (PABLE). On the contrary, the uncertainties of the WT models cause the fatigue due to the mechanical stresses. To overcome these two problems, dynamic sliding mode control (D-SMC) is used because it is robust against uncertainties and can suppress the chattering by providing smooth signals. In D-SMC, an integrator is located before the actuator, as a low-pass filter, to suppress the high-frequency chattering. Then, the states number of the overall augmented system is one more than the states number of the actual system. To control such an augmented system, the added state variable needs to be estimated and hence, a novel sliding mode observer (SMO) is proposed. A trusty comparison is also presented using the conventional sliding mode control (C-SMC) with the proposed SMO. To implement D-SMC and C-SMC, a new state feedback is applied to the turbine at first. Therefore, a linear model with uncertainty is obtained, where its input is the PABLE. Lyapunov theory is used to proof the stability of the proposed SMO, D-SMC, and also the C-SMC. The presented comparison demonstrates the advantages of the D-SMC with respect to the C-SMC in removing the chattering and simplicity in concept and in implementation.
“…The WTFS cannot capture the maximum power of the wind in various wind speeds (Poultangari et al, 2012) and hence, WTVS is developed in recent years (Oh et al, 2015). The strategy to obtain the maximum power of the wind by WTVS, is based on dividing the operation performance using the rated speed of the wind (Jabbari Asl and Yoon, 2016). Below this rated wind speed, the torque of generator is controlled for the maximum power point tracking (MPPT) (Ardjal et al, 2018), and above this rated wind speed, the pitch angle of the blades (PABLE) is used as the input control (Asgharniaa et al, 2018).…”
In a wind turbine (WT), the maximum power can be achieved using a suitable and smooth signal, which should be applied to the pitch angle of the blades (PABLE). On the contrary, the uncertainties of the WT models cause the fatigue due to the mechanical stresses. To overcome these two problems, dynamic sliding mode control (D-SMC) is used because it is robust against uncertainties and can suppress the chattering by providing smooth signals. In D-SMC, an integrator is located before the actuator, as a low-pass filter, to suppress the high-frequency chattering. Then, the states number of the overall augmented system is one more than the states number of the actual system. To control such an augmented system, the added state variable needs to be estimated and hence, a novel sliding mode observer (SMO) is proposed. A trusty comparison is also presented using the conventional sliding mode control (C-SMC) with the proposed SMO. To implement D-SMC and C-SMC, a new state feedback is applied to the turbine at first. Therefore, a linear model with uncertainty is obtained, where its input is the PABLE. Lyapunov theory is used to proof the stability of the proposed SMO, D-SMC, and also the C-SMC. The presented comparison demonstrates the advantages of the D-SMC with respect to the C-SMC in removing the chattering and simplicity in concept and in implementation.
“…Whereas, in the high wind speed region, wind turbines (WTs) are operated to maintain the generated power at its nominal value by controlling the pitch angle and the generator torque. Designs such as proportional integral derivative (PID) control [3], neural network based-PI control [4], optimal control [5], linear parameter varying (LPV) control [6], gain scheduling [7], robust control [8], adaptive control [9] and fuzzy logic control [10] have traditionally been considered to control wind turbines. However, these solutions fail to operate satisfactorily and exhibit limited control action in the presence of faults.…”
This paper proposes an adaptive fault tolerant control (FTC) design for a variable speed wind turbine (WT) operating in the high wind speeds region. It aims at mitigating pitch actuator faults and regulating the generator power to its rated value, thereby reducing the mechanical stress in the high wind speeds region. The proposed FTC design implements a sliding mode control (SMC) approach with an adaptation law that estimates the upper bounds of the uncertainties. System stability and uniform boundedness of the outputs was proven using the Lyapunov stability theory. The proposed approach was validated on a 5 MW three-blade wind turbine modeled using the National Renewable Energy Laboratory’s (NREL) Fatigue, Aerodynamics, Structures and Turbulence (FAST) wind turbine simulator. The controller’s performance was assessed in the presence of several pitch actuator faults and turbulent wind conditions. Its performance was also compared to that of a standard SMC approach. Mitigation of blade pitch actuator faults, generation of uniform power, smoother pitching actions and reduced chattering compared to standard SMC approach are among the main features of the proposed design.
“…The control strategy which is called maximum power point tracking (MPPT) leads to maximise captured power when wind speed is below its rated value. In literature, different control algorithms are proposed to maximise the power and to track the variable angular velocity, starting from proportional–integral–derivative output feedback control [10, 11] to adaptive control [12, 13]. However, due to the aerodynamic interaction, the MPPT strategy of each turbine does not lead to maximal total power capture across the entire wind farm.…”
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.